TRANSFORMERS AND NATIONAL GRIDS

3 marks · Normal

Explain what would happen if only step-up transformers (no step-down transformers) were used in the National Grid. Give two consequences for users and one for the safety of the system.

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Electricity supplied to homes and factories would be at dangerously high voltages, causing risk of electrocution and equipment damage. Most appliances would not work. There would also be much greater risk of fires or accidents.

Also accept: Power would not be suitable for use; System would be unsafe for the public

Common mistakes: Saying homes 'would have no power' (unless justified); Missing the safety aspect

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Marking points

B1 · 1 mark · Identifies supply to users would be at high voltage (unsuitable for appliances)

B2 · 1 mark · States appliances/devices would not work or would be damaged

B3 · 1 mark · States safety issue (danger of electrocution/fire etc)

Worked solution

If only step-up transformers were used, the voltage at users' premises would be extremely high. Normal electrical devices would not be able to function or would be destroyed by the high voltage. It would also be very dangerous, with a great risk of electrocution or fire.